Baxi
Baxi Expansion Vessel Maxflow WM 247431
Baxi expansion vessel 247431 for Maxflow Combi WM appliances, cushioning pressure spikes in the heating circuit.
At a glance
- Part type: Expansion vessel
- Also known as 1116360
- This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.
£117.60
£98.00 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Baxi expansion vessel for the Maxflow WM is a small pressurised tank fitted within the appliance. A charge of air inside the tank is separated from the system water by a diaphragm, and that air cushion absorbs the expansion of water as it heats up, holding system pressure within safe limits. It is a direct replacement component for Baxi Maxflow Combi WM appliances.
Signs this part needs replacing
- System pressure rises sharply as the appliance heats and falls back once it cools.
- The pressure relief valve discharges water during normal heating cycles.
- The pressure gauge reads high with the system cold.
- The system needs frequent topping up to hold pressure.
- Water appears at the air valve on the vessel, pointing to a failed diaphragm.
Before you order
- Check the GC number on the appliance data badge against the compatibility list.
- Confirm the previous part numbers 5120780 and 1116360 against the appliance before ordering.
- This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.
Mechanical
| Part type | Expansion Vessel |
|---|
Compliance
| Manufacturer part number (MPN) | 247431 |
|---|---|
| GC number | E59-869 |
| Barcode / EAN | 5039177615972 |
| Commodity code | 8403 90 00 00 |
| GPC classification | Household Boilers/Furnaces/Tank Water Heaters Replacement Parts/Accessories |
| Alternative numbers | 5120780, 1116360 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| BAXI BAXI MAXFLOW COMBI WM | — | — | — | |
| BAXI MAXFLOW COMBI WM | 47-075-03 | 47-075-03 | — | — |
Documents & drawings
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